1. Field of the Invention
The present invention relates to a voltage nonlinear resistive element and a method for manufacturing the voltage nonlinear resistive element.
2. Description of the Related Art
Voltage nonlinear resistive elements (varistors) are elements having a structure in which a voltage nonlinear resistor is disposed between a pair of electrodes, and are widely used as elements for protecting electronic circuits from abnormal voltage in various sensors, such as humidity sensors and temperature sensors. Patent Literature 1 discloses a voltage nonlinear resistive element of this type in which a resistor is disposed between a pair of electrodes, wherein the resistor has a structure in which a zinc oxide ceramic layer is joined to a metal oxide layer represented by M1-xAxBO3 (M: rare-earth element, A: at least one of Sr and Ba, B: at least one of Mn and Co, x≦0.4). The resistor is produced by joining a green zinc oxide ceramic and a green metal oxide and sintering them as one body at a temperature in the range of 1200° C. to 1350° C. The zinc oxide ceramic layer has a specific resistance in the range of 0.001 to several ohms mm (10−4 to 10−1 of ohms cm). The specific resistance is identical to volume resistivity.